A comprehensive study is to be made of BALB/c murine myeloma. This transplantable tumor system will be used as a model system to study various different biological, virological, immunological and biochemical aspects of these malignant lymphoid cells. Studies to be carried out will (1) examine the mechanism of genetic regulation of macromolecular, in particular immunoglobulin, synthesis; (2) characterize the tumor specific antigens of myeloma; (3) examine the relationship between the tumor cell and the intracisternal A-type particles and extracellular C-type particles associated with it; (4) to characterize the myeloma intracisternal A-type particles and C-type particles as to their biological, immunological, and biochemical properties; (5) examine the host response to and interaction with the transplanted tumor.